Charles Spurgeon Commentary Isaiah 7:5-9

"Because Syria, Ephraim, and the son of Remaliah, have purposed evil against thee, saying, Let us go up against Judah, and vex it, and let us make a breach therein for us, and set up a king in the midst of it, even the son of Tabeel; thus saith the Lord Jehovah, It shall not stand, neither shall it come to pass. For the head of Syria is Damascus, and the head of Damascus is Rezin; and within threescore and five years shall Ephraim be broken in pieces, so that is shall not be a people: and the head of Ephraim is Samaria, and the head of Samaria is Remaliah`s son. If ye will not believe, surely ye shall not be established." — Isaiah 7:5-9 (ASV)

Because Syria, Ephraim, and the son of Remaliah, have taken evil counsel against thee, saying, Let us go up against Judah, and vex it, and let us make a breach therein for us, and set a king in the midst of it, even the son of Tabeal: thus saith the Lord GOD, It shall not stand, neither shall it come to pass. For the head of Syria is Damascus, and the head of Damascus is Rezin; and within threescore and five years shall Ephraim be broken, that it be not a people. And the head of Ephraim is Samaria, and the head of Samaria is Remaliah's son.

God did not intend it to grow any bigger. These two little kingdoms of Syria and Ephraim were to keep as they were until they were destroyed.